Fiedor Joanna, Przetocki Mateusz, Siniarski Aleksander, Gajos Grzegorz, Spiridis Nika, Freindl Kinga, Burda Kvetoslava
AGH-University of Science and Technology, Faculty of Physics and Applied Computer Science, 30-059 Kraków, Poland.
Jagiellonian University Medical College, 31-202 Kraków, Poland.
Antioxidants (Basel). 2021 Mar 13;10(3):451. doi: 10.3390/antiox10030451.
β-Carotene (β-Crt) can be dispersed in hydrophobic regions of the membrane of red blood cells (RBC). Its location, orientation and distribution strongly depend on carotenoid concentration. In the present pilot trial (six human subjects involved), it is demonstrated that incubation of RBCs with β-Crt (1.8 × 10 β-Crt molecules per RBC, 50 μmol/L) results in expansion of the membrane of RBCs and slight elongation of the cell. The changes are of statistical significance, as verified by the Wilcoxon test at < 0.05. They indicate (i) a highly random orientation and location of β-Crt inside the membrane and (ii) a tendency for its interaction with membrane skeleton proteins. The accompanying effect of decreased RBC resistance to lysis is possibly a result of the incorrect functioning of ion channels due to their modification/disruption. At higher β-Crt concentrations, its clustering inside membranes may occur, leading to further alterations in the shape and size of RBCs, with the most pronounced changes observed at 1.8 × 10 β-Crt molecules per RBC (500 μmol/L). Due to the reduced permeability of ions, such membranes exhibit increased resistance to haemolysis. Finally, we show that interactions of β-Crt with the membrane of RBCs lead to an alteration in haemoglobin-oxygen affinity, shifting the oxyhaemoglobin dissociation curve toward higher oxygen partial pressures. If the impact of β-Crt on a curve course is confirmed in vivo, one may consider its role in the fine tuning of O transportation to tissues. Hence, at low concentrations, providing unchanged elastic and functional properties of RBCs, it could serve as a beneficial agent in optimising heart performance and cardiovascular load.
β-胡萝卜素（β-Crt）可分散于红细胞（RBC）膜的疏水区域。其位置、取向和分布很大程度上取决于类胡萝卜素浓度。在本次初步试验（涉及6名人类受试者）中，结果表明，用β-Crt（每个RBC含1.8×10个β-Crt分子，50μmol/L）孵育RBC会导致RBC膜扩张以及细胞轻微伸长。这些变化具有统计学意义，经Wilcoxon检验，P<0.05得以验证。它们表明：（i）β-Crt在膜内具有高度随机的取向和位置；（ii）其与膜骨架蛋白存在相互作用的趋势。RBC对裂解的抵抗力下降这一伴随效应可能是由于离子通道的修饰/破坏导致其功能异常所致。在较高的β-Crt浓度下，其可能在膜内聚集，导致RBC的形状和大小进一步改变，在每个RBC含1.8×10个β-Crt分子（500μmol/L）时观察到最明显的变化。由于离子通透性降低，此类膜对溶血的抵抗力增强。最后，我们表明β-Crt与RBC膜的相互作用会导致血红蛋白-氧亲和力改变，使氧合血红蛋白解离曲线向更高氧分压方向移动。如果β-Crt对曲线进程的影响在体内得到证实，则可考虑其在向组织精细调节氧气运输中的作用。因此，在低浓度下，在保持RBC弹性和功能特性不变的情况下，它可作为优化心脏性能和心血管负荷的有益物质。
